A source told British magazine Grazia that five months after Russell filed for divorce, he wrote his ex-wife of 14 months a teary e-mail expressing his regret, saying divorce was a mistake and that he gave up on the marriage too quickly.
While this may seem sweet and sincere at first glance, those close to the couple say Russell is "seething with jealousy" after spotting pictures of Katy nuzzled up next to Florence + the Machine guitarist Robert Ackroyd at this past month's Coachella music festival.
Certainly Russell has rebounded — he's been linked to Hungarian model Nikolett Barabas and numerous other pretty brunettes — but seeing Katy linked to another shaggy Brit may have been the added punch needed for him to attempt a reconciliation.
However, the two mending bridges is unlikely. Sources say they split because the recently sober Russell couldn't handle Katy's partying, which, if recent pictures serve as any evidence, hasn't slowed down in the slightest.
For access to all our exclusive celebrity videos and interviews – Subscribe on YouTube!