The political mercury is rising as the opposition bloc warms up for another challenge to Prime Minister Prayut Chan-o-cha, this time in the form of a planned no-confidence motion.
Capt Thamanat Prompow, leader of a breakaway faction from the ruling Palang Pracharath Party (PPRP) and now secretary general of newly formed Setthakij Thai, has warned Gen Prayut of a nasty surprise as people in the government camp could act against him during the House debate.
Recent weeks have seen the unusual endeavour of certain political factions trying to give the impression that Deputy Prime Minister Prawit Wongsuwon would be an appropriate choice for the next premier, should the incumbent eventually trip up politically.
If Gen Prayut were to lose the House no-confidence vote, he would be sent packing.
While some observers have ruled out such a scenario, it's not impossible given that every party now has its own aspirations.
Initially, the opposition planned to file for no-confidence as soon as the House reconvenes on May 22 amid speculation the PM would opt to dissolve the House.
The no-confidence move would be a guarantee against this, as stipulated by the 2017 charter.
However, the opposition has reason to delay such a move as they must see to it that crucial bills, including those relating to elections and political parties as well as the 2023 budget bill, go through the House.
In terms of timing, July would be better for a non-confidence motion as Gen Prayut's tenure, including the time he ran the country as junta leader, will reach eight years in late August.
The 2017 charter caps a PM's tenure at eight years, successive or not. But government supporters want the count to begin in 2019 when Gen Prayut took office after the March 24 elections. The opposition plans to petition the Constitutional Court about this.
Setthakij Thai, with Gen Wit Devahastin na Ayudhya -- Gen Prawit's close aide -- as party leader, has 18 members. There is talk the party may side with the opposition in the forthcoming debate.
But to achieve its goal, Capt Thamanat -- who wants vengeance after the PM expelled him from the cabinet in January -- needs help from smaller coalition parties as half of the House is required for a no-confidence attempt.
This is why the smaller parties get together every week. It's known that pre-House debates are a time for bargaining, with some members of smaller parties allegedly raking in millions of baht in exchange for their votes.
Yet many analysts are not convinced Capt Thamanat and those small parties would succeed as a "band of brothers", as the bond among Gen Prayut, Gen Prawit and Gen Anupong Paojinda is perhaps too strong.
It is said that Gen Prawit, the biggest brother and head of the PPRP, would love to see the government complete its term next March and stage a comeback after the 2023 elections, rather than break up with his brothers-in-arms. Any foul play would put him in a hard situation as well.
Speculation of Gen Prawit taking the baton from his brothers-in-arms came from a pro-democracy faction known as the families of May 1992 heroes, under Adul Khiewboriboon, wherein Gen Prayut could not survive the no-confidence debate and with a view to a looming crisis surrounding his questionable eight-year tenure. Pro-democracy factions as well as some key figures of the yellow and red groups, among them Suriyasai Katasila, Jatuporn Prompan and others, also share the idea.
These political groups have been upset and disillusioned by Gen Prayut's failure to keep his promises on political resolutions and an amnesty for lesser-known political activists who were thrown into prison over colour-coded conflicts. He has effectively ignored recommendations by reconciliation panels. Worse, Gen Prayut has been insincere regarding a charter amendment, a process many hoped would lead the country out of its political deadlock.
This is the May 1992 group's outline: Deputy Prime Minister Gen Prawit steps in for the remaining 10 months before the next election. During the transitional period, he would form a national government that comprises all parties, while seeing to it that a new charter is drafted and that political prisoners receive a pardon. Such a caretaker government likewise would tackle economic problems.
Several observers have derided Mr Adul's proposal as a pipe dream. Yet the leader of the May 1992 group maintains that Gen Prawit has certain strengths given he still has connections with fugitive ex-premier Thaksin Shinawatra and the Pheu Thai Party, and has control over the 250-member Senate. As the most senior deputy prime minister, and head of the PPRP, he is "fit" for the top job.
But that would be a rough process. It must begin with Gen Prayut's downfall, which would be quite difficult in the view of many observers. Yet Capt Thamanat and other small-party politicians are working on a plan to isolate the prime minister. If their plan succeeds, Gen Prawit may have a chance to lead, albeit for a short period.
There are two possibilities.
One sees parliament return to its normal process, searching from the list of candidates proposed by political parties in accordance with Section 88 of the charter, which requires that at least half of parliament must vote, or a minimum of 376 out of 750. On the list are Deputy Prime Minister and Health Minister Anutin Charnvirakul of the Bhumjaithai Party, Abhisit Vejjajiva of the Democrat Party and Chaikasem Nitisiri from Pheu Thai. Of the three, Mr Anutin is the most likely choice.
The other sees Gen Prawit take over as ad hoc leader. This option requires 500 votes from a total of 750 in both the Upper and Lower Houses. Perhaps the most likely outcome would be 250 votes from the Senate and another 250 from coalition parties, including support from the newly formed Setthakij Thai.
But for this to become reality, Gen Prawit would have to break a vow with his brothers-in-arms. Would big brother dare to do so?