Mark and Ross square up to each other in Monday night's EastEnders on RTÉ One and BBC One.
Sharing first-look photos, the BBC soap said: "Ross plans to propose to Vicki, but sparks fly when protective brother Mark learns of his intentions and opposes the idea, still wary after everything she went through with Joel."
Fans can watch what happens next on Monday on RTÉ One and BBC One at 7:30pm.
EastEnders airs on RTÉ One and BBC One Monday to Thursday.